How can you determine the rate-determining step of a 3-step mechanism if they are not labeled fast or slow?

A) Analyze the experimental rate law to see which step it aligns with.
B) Investigate the intermediates' concentrations and their impact on the overall rate.
C) Conduct kinetic experiments at varying conditions to observe the step that influences the rate the most.
D) Use theoretical calculations or modeling to estimate the activation energies of each step.